Steering gear for vehicles



Nov. 29, 1932. A. FLETTER 1,889,728

STEERING GEAR FOR VEHICLES Nov. 29, 1932. A. FLETTNER 1,889,728

STEERING GEAR FOR VEHICLES Filed-June 27, 1929 2 Sheets-Sheet 2 Patented Nov. 29, 1932` i `UNITED STATES IPATENT 'oFFIcai Application filed .Tune 27, 1929, Serial No. 374,247, and in Germany July 5, 1928.

My invention relates to improvements in tion on these steering memberskwhereby the steering gear for vehicles, more particularly' main wheels are 'similarlydeflected automotive vehicles. Preferably the connection between the The main object of Amy invention is to` wheels is such that accidental deviations ofy 5 provide mechanism by means of which vethe main wheels areautomatically redressed 55 hicles may be steered far more easily and by th-e auxiliary wheels. 1 quicker than is possible with the mechanism In ,the drawings aiiixed lto andyforming heretofore employed for the purpose. part of this specification three embodiments According to my invention the angularly of my invention are illustrated diagrammatoscillatable4 main wheels of an automotive icallyby way of example,butit will be read' 60 vehicle are not directly steered by the hand ily understood that my invention is by no of the driver through a steering gear, but means confined to the examples illustrated one or a plurality of auxiliary wheels are and described, and that .any arrangement provided which partake in the support of the utilizing the broad underlying principle of vehicle and which are cont-rolled directly by my invention falls Within ythe ambit of my 65 the driver with the aid of suitable steering claims. gear. These auxiliary Wheels are connected In the drawings i with the main wheels in such manner that on Fig. 1 is a plan of the chassis of an auto? the auxiliary wheels being angularly deflectmotive vehicle in which two main wheelsare ed by the steering gear handled by the driver, steered by two auxiliary wheels located in 70 they will cause an angular deflection of the front o-f the main wheelswhile Y V main'wheels. In other words, it is not the Fig. 2 is al side-elevation'of'the vehicle, steering gear operated by the driver that di- Fig. 3 is a plan View of the 'chassis of. a rectly dellects the main wheels, but the auxmodified form of vehicle in which the auxz iliary wheel or wheels will steer the main iliary wheels are llocated behind the main 75 wheels. wheels steered by them, and Y i In a preferred embodiment of my inven- Fig. l is a similar view of a third modificaj` Y y tion each main wheel is arranged for rotation tion. Y y

at one end, preferably the end of the shorter Like parts are indicated by like numerals arm, of a double-armed steering member of reference throughout all thefigures of the 80, mounted on some part of the vehicle frame drawings. f for oscillation about a substantially vertical Referring to Figs. 1 and 2 of the draw' axis. An auxiliary wheel is oscillatably ings, 11 is-the chassis 4or underframe of an mounted at the other end of Vone or each automotive-vehicle, 12 thecoachwork ofthe steering member and steering gear extendcar, 13 the motor, 14e` and 114 the gear which 85 ing from the drivers seat to the auxiliary transmits powervfrom the engine to the rear wheel or wheels is connected with these axle 15H16 and 17 are therear wheels. The wheels in such manner that by operating angularlyoscillatable front main wheels are the steering gear the auxiliary wheel or marked 18 Vand 19. 23 and 24 are two auxilwheels can be angularly deflected. Obviousiary wheels. ly the deflection of a wheel or wheels car-V The weight of the car rests at 20, 21 on the rying only a comparatively small, if any, rear frame of thevehicle and is supported by part of the weight of the vehicle can be efthe axle in such -a manner that the point fected far more easily and lquickly than that of support'of that part of the weight of the 5 of a pair of main wheels loaded with about car which is apportioned to the front wheels 95 one-half of the total weight ofthe vehicle. is nearer the center of the main wheels 18, 179

By virtue of their being operatively connectthan the center of the auxiliary wheels 23,

ed with the main wheels by the oscillatable 24C, so that the latter wheels are called upon steering members, the auxiliary wheels will to carry only a small portion of the weightA transmit their movement of angular detlecof the car. The axle 30, carries in its turn 1001 steering members 31, 32, each of which in the example illustrated is formed in one piece, but may also consist of a plurality of articulated pieces. The steering members are arranged for vertical oscillation about this axle with sleeves 40, 41 and for horizontal oscillation about pins 65, 66 mounted on these sleeves. On the short arms of the steering members are mounted the main wheels 18, 19, their axles 43, 44 being fixed to the ends of the steering members, while the auxiliary wheels are pivoted to the ends of the longer arms of those members by' means of the stump axles 33, 34,'so that the: auxiliary wheels can oscillate with theirfstump axles 47, 48 about the vertical pins 49 and 50 mounted on the steering members of the connecting point.

The steering gear consists of a suitable steering mechanism, for instance the steering wheel 54, which in the conventional manner, for instance, a worm and wormwheel 55, 56 acts upon the rod 57 which by means of a pinv 58 engages an auxiliary steering lever 59,

t tion of the connecting frames 31, 32.

which is oscillatably mounted on the pin formingthe pivot for the steering member 31. By a pin on the lever 59 is engaged another rod 72 which in turn engages the main steering lever V7 4. The steering lever is mounted for oscillation on the pin 49 fixed to the end of the steering lever and is rigidly fixed to the stump axle 33' of the auxiliary wheel 23. To the parts 59, 72, 74 correspond ,similar steering gear parts 60, 73, 75 at the other side of the car. Arms 78, 79 forming bell-crank levers with the levers 59 and 60 respectively are pivotally connected at 80, 81 by a rod 82, while another rod 83 pivotally n connectsthe endsof the steering members by means of the pins 49, 50. `If by means of the steering gear 54, 55, 56, 57, '58, 72, 74 the auxiliary wheel 23 is deflected, the steering wheel 24 at the other side is similarly deflected by vmeans of the connecting gear 78,

82, 79 andvsteering levers 60, 75.

If the vehicle is in motion, the deflection of the auxiliary wheels 23, 24 will bring about the steering of the main wheels 18, 19 by causing .l the steering members 31, 32 to oscillate about CDUYV their vertical pivots 65, 66, whereby the main steering wheels are also angularly displaced relative to the vehicle frame and steer the vehicle in the usual manner. In the normal j position the vertical pivots 65, 66, 49, 5() are i located on the corners of a rectangle and when displaced will form a parallelo-gram, so that the steering Ymembers at both sides of the vehicleV are alwaysturned in the same direction and to the same extent.

In order to limit an accidental deviation of the main wheels and steering levers stops 87, 88 are provided at suitable points, for instance on the axle 30, which limit the deflec- The stops are preferably made elastic by provid# ing, for instance, resilient cushions 89, 90 of rubber, leather, springs or the like.

The mechanism illustrated is not only suitable for adjusting the main wheels, but it will also serve to correct any accidental and undesirable movement of the main wheels and to return them into the desired position by the very deflection of the auxiliary wheels resulting from such accidental movement of a main wheel. In case of such an accidental deflection ofl a main wheel, for instance on slippery ground, during which, for instance, the auxiliary steering lever 59 and the main steering lever 74 are arrested in their normal position by self-locking gears 55, 56, inserted in the steering gear, the steering member 31 may be swung around the pin 65, whereby the pin 49 on the other end of the steering mem-A ber, which engages the inner end of the main steering lever74 and the stump axle 47 of While changing its angular position relative to the steering member 31, is not deflected relative to the vehicle frame and the direction of travel, but is merely displaced sideways in parallel to its former position and,

being in positive steering connection lwith the main Wheel, will cause the steering member 31 to swing back into normal position, carrying the main wheel with it, without the driver being required to operate the steering gear. Obviously this correction of an laccidental deflection of the main'wheels will take place in any position, even in the steering positions of the main wheels.

The degree-of correction may be predetermined by a suitable choice of the leverage or transmission ratio. If, for instance, the auxiliary steeringlever 59 is made longer than the main steering lever 74, a considerable corrective effect is obtained. If the main steering lever 74 is made longer than lever 59, the effect of the correction is less. As a rule the .lever 74 will be made longer than the lever 59, because then favorable steering conditions result and in particular less power is required for steering. It will be obvious that the position of the levers 74, 75, which is adjusted from the drivers place, determines the position which the main wheel should assume and which it retains also under the influence of the correctivemotion, even in the case of disturbances caused'by the track.

The pivots of the auxiliary steering levers'59 and 60 are preferably made to coincide with the axes of oscillation, of the steering members 31, 32, because the control as well as the correction action is thus rendered simple and may easily be determined in advance for all positions.

In the modification ofl my invention illus` trated in Fig. 3 of the drawings the auxiliary' wheels 123, 124 are located to the rear of the main wheels 18, 19. In principle the arrangement is, however, the saine as described with reference to Figs. 1 and 2 of the drawings. A dii'erence exists in so far as the longer arms of the steering members 131, 132 now extend rearwardly and the auxiliary steering lever 159 has an outer extension 259 bevond its pivot point.; The lever arms 259,

174 and 260, 175, respectively, which are conl nected by rods 172, 173, now turn in opposite directions. This is necessary in order to obtain the correct correction eliect, as otherwise due to the arrangement of the auxiliary wheels to the rear of the main wheels the turning of these levers in the same direction would result in a negative correction increasing, instead of redre-ssing, the unintentional deliection of the main wlieel.

Fig. 4 of the drawings illustrates a further modification in which the engine 13 acts through the diiierential gear 214, the Cardan joints 215, 216, the front wheelaxles 217 and 218 and Cardan joints 219, 220 on the frontmain wheels 228,- 229. The Vpivots 233, 234 of the steering members 231, 232 are located in the center ot the main wheelsf228, 229. The vertical pivots 240, 241 of the auxiliary wheels 244, 245 carried by the steering members 231, 232 are likewise located in the'center Otherwise the a-rof the auxiliary wheels. rangement is the sam-e as described above. The weight of the front portion-V of the car rests here on the lixed transverse axle 250 by means of oblique connecting pieces 253, 254, which are mounted on bearings 256, 257 of the fixed axle 250.*In this way a part of the load of the car is transferred onto the auxiliary wheels. The steering mechanism corresponds otherwise with the one described before and operates in the same manner.

In the embodiments described by way of example the number of auxiliaryrwheels corresponds to the number of dirigible main wheels, but a lesser or greater number of auxiliary wheels may be provided. It is furthermore not necessary that the auxiliary wheels should have the same gauge as the main wheels, or that the front wheels should loeV steered, as the rear wheels might equally well be dirigi'ble and governedby the auxiliary wheels.A Other modifications will suggest themselves to those skilled in the art.

Various modiiications and changes may be made without departing from the spirit and scope of the invention, and I desire, therefore,

that only such limitations shall be placed thereon as are imposed by the prior art.

I claim as my invention:

1. Automotive vehicle comprising aI vehicle main frame, a main wheel oscillatable about substantiallyvertical axis'relative to said frame, a steering member oscillatable about the same vertical axis as said main wheel and forming adouble-armed lever havmember, an auxiliary'wheel rotatable about al horizontal axisat one endof said steering lever and hand steering gearconnected to the other end ofsaid steering lever.v

3.Automotive vehicle comprising a vehicle frame, a steering member mounted on said frame forv oscillation'about a substantially vertical axis', a mainl wheel rotatable about a horizontal `axis at oneEY end of said l,steering member, aA main steering f' lever oscillatably' mounted near the" other end of said steering member, an auxiliary wheel ro'- tatable about a horizontalaxis at'one end of said steering lever, an auxiliary steering lever` oscillatable about the axis of oscillation ot said steering member and hand steering gear connectedto said steering levers. e

L4. Automotive vehiclecomprising a vehicle frame, a steeringmembermounted on said ira-me Vfor oscillation about a substantially vertical axis,-a main wheel rotatable about Va horizontal axis at one end of saidy steering member, a main steering lever oscillatably mounted near the other end-of said steering member, anauxiliary'wheel rotatable about a horizontal axis at o ne'end oi said steering lever, an auxiliary steering lever oscillatable about the axis of oscillation of said steering member` and hand steering gear connected to said steering levers, the'operative l'engthotl said main steering lever being'greater than that of said auxiliary steering lever.-

f 5.V Automotive vehicle comprisingl a vehiclefframe, a steering member mounted onsaid frame for-oscillation about a substantially vertical axis, a main wheel rotatable about a horizontal axis at oneV end of said steering member, a main steering lever -oscillatably mounted near the other end of said steer- Y ing member, an auxiliaryv wheel rotatable about a horizontal axis at one end of said steering lever, anauxiliary steering lever oscillatable about the axis of oscillation of said steering member and hand steering gear connecting said steering levers so as to keep said levers inparallel throughout the steeringoperations. i a l 6. Automotive vehicle comprising a vehicle frame, two steering members, one on each side of said frame, mounted for oscillation about substantially Y vertical axes, a main wheel rotatable yabout ahorizontal axis at one end of each steering member, an auxiliary* Wheel oscillatably mounted nearthe other end of each of said steering members, hand steering' gear operatively connected with one of said'auxiliary wheels and a connection between said auxiliary Wheels.V

7. Automotive vehicle comprising a vehicie frame, two steering members, one on eachside'oi:l said frame, mountedfor oscillation about substantially vertical axes, a main f wheelrotatable about arhorizontal axis at one Vend of each steering member, a main steering lever osc'illatably mounted near the other end of each steering member, an a'uxil iary wheel'rotatable about a horizontal axis at one end of each main steering'lever, anj

auxiliary steering-leveroscillatable aboutthe axis of oscillation( of each steering member and hand steering'gear` connected to said steering levers. g ,y 'Y n 8. Automotive' vehicle comprising a vehicle frame, .twosteering members, one on each side otfrsaid ifi'ame,'mo nntedfor oscillation abouti substantially Yvertical axes, a main Wheel rotatable vabout ahorizontal axis 'at `*one end ot each steer-ingv member, afmain steering llever oseillatably mounted' near the iary wheel rotatable about a horizontal axis at one end of each mai-n steering lever, an Vauxiliary steering lever oscillat'able about the axis of oscillation of each steering memberV` an'dhand steering gear` connected to said vsteering'lev'ers, the mainand auxiliary levers on 'the same side of the frame extending in opposite' directions. f f

9. Automotive'vehicle comprising a main vehicleframa'two steering members one on each side'Cif-said'fra1ne,vmounted Jfor oscillai tion about substantiallyvertical axes, 'a main vwheel rotatable about `a horizontal' axis at one end of each steering member, an auxiliary. wheel oscillatably mounted near the vother end of each of said steering members and carrying part'of the weight of said-main frame, hand steering gear operatively connected Withone of said auxiliary wheels and a con-V nection between said auxiliaryV Wheels.

In testimony whereof I aiix my signature; ANTON LETTNE'R.

CERTFICATE 0F CQRRECTION.`

Patent No. '21889, 728. November 29, 193:2.'v

ANTON FLETTNER.

it is hereby certified that error appears inthe printed specification ofthe above numbered patent requiring correction as ioiiows: Page 1, line 7, for "mechanism" read "mechanisms"; page 2, line 17, before "mounted" insert the word "respectively-' and lines 17 and 1S, strike out the words "of the connecting point"; line 29, before "steering" second' occurrence, insert the word "main"; line 34, strike out the words "steering gear"; and line 60, for "deviation" read "deilecion"; page 3, line 62, claim 1, after "about" insert the article "a"; and that the said Letters Patent should be read with these correetions therein that the same may conform to the reeerd of the case in the Patent Office,

Signed and sealed this 24th day/.of January A. D. 1933.

M. J. Moore, (Seal) v Acting Commissioner of Patents. 

